[ruby/optparse] Add EditorConfig file

More info here: https://editorconfig.org/

For example, `ruby/ruby` has it: https://github.com/ruby/ruby/blob/05ebaee/.editorconfig

Also fix some offenses.

https://github.com/ruby/optparse/commit/29402e7e0e

misc/rb_optparse.bash

@@ -17,5 +17,5 @@ _rb_optparse() {
 }
 
 rb_optparse () {
-    [ $# = 0 ] || complete -o default -F _rb_optparse "$@"
+  [ $# = 0 ] || complete -o default -F _rb_optparse "$@"
 }

misc/rb_optparse.zsh

@@ -25,8 +25,8 @@ generate-complete-function/ruby/optparse ()
     mkdir -p "${ZSH_COMPLETION_DIR-$HOME/.zsh.d/Completion}"
     $1 "--*-completion-zsh=${1:t}" >! "${ZSH_COMPLETION_DIR-$HOME/.zsh.d/Completion}/$cmpl"
     if [[ $(type -w "$cmpl") == "${cmpl}: function" ]]; then
-	unfunction "$cmpl"
+        unfunction "$cmpl"
-	autoload -U "$cmpl"
+        autoload -U "$cmpl"
     else
         compinit "$cmpl"
     fi

test/optparse/test_acceptable.rb

@@ -196,4 +196,3 @@ class TestOptionParser::Acceptable < TestOptionParser
   end
 
 end
-